Lock.



I. D. MERRITT.

LOOK.

APPLIOATION FILED JULY 22, 1911.

1,085,817, Patented Feb. 3, 1914.

2 SHEETS-SHEET 1.

WITNESSES: Y 11v VENTOR.

mjaw $211M BY a W I figka/fle #12 A TTORZVEY.

COLUMBIA PMNOhRAPH CDWWASMWGTON, D. c.

I. D. MERRITT.

LOOK.

APPLIOATION FILED nrLYsz, 191i.

Patentd Feb. 3, 1914.

2 SHEETS-SHEET 2.

w 0 OJ 2 INVENTOR.

BY K

W[TNESSES.-

7Q. A? W ATTORNE I UNITED sTA ns PATENT OFFICE. A

IRVING D. MERRITT, OF NEVT HAVEN, CONNECTICUT, ASSTG'NOR T0 SARGENT & COMPANY, OF NEW HAVEN, CONNECTICUT, A CORPORATION OF CONNECTICUT.

LOCK.

Specification of Letters Patent.

Application filed July 22, 1911.

Patented Feb. 3,1914. Serial No. 640,026.

To all whom it may concern Be it known that I, IRVING D. MERRITT, of the town of New Haven, in the county of New Haven and State of Connecticut, have invented new and useful Improvements in Locks, of which the following is a full, clear, and exact description when taken in connection with the accompanying drawings, which form a part thereof.

My invention'relates to looks, and its primary objects areto provide means of an improved character for preventing a door from being locked from the outside when it has been previously locked from the inside, and to provide simple and effective means for dogging an outside knob or other member as the door is locked from the inside, thereby indicating to any one on the outside that the room is occupied.

To these and other ends my invention'is embodied in preferable form in the device hereinafter described and illustrated in the accompanying drawings.

In the drawings, Figure 1 is a side view of the lock with the cap plate removed and both dead bolts retracted; Fig. 2, a similar view showing inside deadbolt protracted; Fig. 3, a similar view showing the outside deadbolt protracted by the guest key, with the inside bolt retracted; Fig. 4, a view similar to Fig. 2, with the tumblers removed; Fig. 5, a rear view similar to Fig. 2; Fig. 6, a section through lower bolt and tumblers with emergency key engaged therewith; and Figs. 7 and 8, detail views respectively of the emergency key and guest key.

In all figures, similar letters of reference represent like parts.

Referring to the drawings, 1 is a casing, and 2 a cap plate of a lock. Mounted in the casing is a latch bolt 3 having a shank 4: provided with a cross head 5 which is operatively engaged by the shoulder 6 of a sliding spring pressed yoke 7 retractable by the ordinary knob spindle hub 8. The rear face of the lower arm of the yoke is cut away on an incline at 9 at the inner end of the yoke arm, providing an abutment for a pivoted dog 10, the function of which is to block the movement of the yoke and thus prevent the rotation of the hub and knob. The dog 10 has a depending lug 11, which is alined and in contact with an upwardly projecting arm 12 of an upper deadbolt 13. 7 A lug let on the dog is adapted to contact with a post 15 projecting from the casing for the purpose of limiting the upward movement of the dog.

The belt 13 carries a tumbler stump 16 the upwardly projecting arm 22 of a cou-v pling lever, the other arm 23 0f which lever extends within a slot 24 formed in a lower deadbolt 25, which bolt is adapted to be operated from the outside of the door by means of a key inserted through the keyhole 26. The connection between the two deadbolts provided by the coupling lever serves to effect the retraction from rotracted position of the deadbolt 25 whenever the deadbolt 13 is protracted. Similarly, the protraction of the deadbolt 25 serves to retract the deadbolt 13 when the latter is in protracted position. Owing to the fact that the upper arm 22 of the coupling lever engages the deadbolt 13 merely on one side, namely, toward the forward end of the bolt, the protraction or retraction ofeither bolt when the other bolt is retracted is not interfered with by said couplin lever. The deadbolt 13 is guided and held yieldingly in retracted or protracted position by means of a spring 27 having a shoulder adapted to engage a notch at the under edge of said deadbolt.

The coupling lever is provided with a dogging arm 28 which is adapted to be projected into the path of the key inserted through the inside keyhole by the protracted movement of the inside deadbolt 13 for the purpose of preventing the withdrawal of the key from the keyhole .until the deadbolt 13 has been again retracted by similar slot which engages a tongue 34 of the tumbler 18, whereby as the tumbler mechanism for either bolt is disengaged the tumbler mechanism for the other bolt will simultaneously be disengaged, which arrangement permits or the conjoint action of the two bolts as heretofore described.

Pivoted on the pin 29 behind the tumblers 30 is a movable ward 35 formed similarly to one of the tumblers 30 and adapted to be moved by the bit of a key in the same mannor as said tumblers are moved. This movable ward consists preferably of a bell crank or elbow lever, having an arm 36 adapted to extend into the path of operative rotation of the key bit inserted through the keyhole 26 and another arm 37 adapted to project up wardly into an inclined recess 38 formed in the lower edge of the inside deadbolt 13. The recess 38 provides at its rear end an inclined end portion or shoulder 39 which is adapted to bear against the upper face of the arm 37 so as to force said arm downwardly and hold the stop lever rigidly in a position in which the lower arm interrupts and obstructs the operative rotation of the key bit.

The surface of the projection 30 of the inside bolt which blocks the ward from upward movement with respect to the outside keyhole is located at that edge of the bolt shank which is lowermost with reference to the door to which the lock is applied. The recess 38 in front of the projection 39 accommodates the arm 35 with a certain amount of clearance when the inside bolt is retracted, as shown in Fig. 1, so that when the ward is engaged by the bit of the guest key in the outside keyhole said ward may be freely raised to such an extent as to permit a full rotation of said key for the purpose of protracting the outside bolt.

The operation of the lock is as follows: When it is desired to lock the door from the inside of the room, the guest key is inserted through the inside keyhole 19 and the bit rotated so as to release the tumbler and pro tract the bolt 13. The protracted movement of the bolt by the contact of its arm 12 with the lug 1a of the dog 10 throws said dog back of the yoke 7 and against the inclined surface 9 thereof and thus prevents the rotation of the hub controlling the same. This dogging of the hub prevents the rotation of the knob to indicate when the knob or similar member is tested by the hand of the maid or housekeeper that the door is locked on the inside, thus rendering it unnecessary to insert a key in the outside keyhole for the purpose of trying the lock. Then the inside bolt has been protracted it will be impossible for the key to be withdrawn. without first retracting the bolt, owing to the fact that the arm 28 of the coupling lever lies in the path of rotation of the key and prevents a full rotation thereof. In the protraction of the inside bolt, the inclined shoulder 38 on the lower part of the shank or tail of said bolt will be carried over the arm 36 of the ward 35, as shown in Fig. 4:, thus preventing the upward movement of the ward and holding the lower arm of the latter in the path of the key bit. In this position of the ward, it will be impossible to operate any of the keys sufliciently to release the tumblers or throw the bolt, except the emergency key 10, the bit of which as seen from Fig. 7 is so formed as to enable it to pass the ward and operate the tumblers and the bolt 25. The protraction of the bolt 25 by the emergency key when the bolt 13 is protracted serves by the engagement of the coupling lever with said deadbolts to retract said bolt 13.

In addition to the guest key 20 and emergency key 40, a master key and grand-master key are usually provided. The purposes of these latter keys are well understood in the art and it has not been considered necessary to illustrate such keys.

Having now described my invention, what I claim and desire to secure by Letters Patent, is

1. In a lock, the combination of an outside bolt, an inside bolt, a keyhole for the outside bolt, and a pivoted ward associated with said keyhole and normally out of contact with said inside bolt, said ward being locked in blocking position with respect to said key hole by direct engagement of said ward with the under portion of the shank or tail of the inside bolt when said inside bolt is protracted; substantially as described.

2. In a lock, the combination of an outside bolt, an inside bolt, a keyhole for the outside bolt, a pivoted tumbler for the outside bolt, a key for the outside bolt, and a pivoted ward associated with said keyhole and adapted to be lifted by said key the out side bolt is protracted, said inside bolt having a portion adapted to engage said ward directly when said inside bolt is protracted to prevent the raising of said ward; substantially as described.

3. In a lock, the combination of an outside bolt, an inside bolt having a shank pro vided with a recess and with a projection, 21 keyhole for the outside bolt, a key insertible in said keyhole to actuate said outside bolt, and a pivoted ward associated with said keyhole and movable by said key, and having a part adapted to operate in said recess of the inside bolt when the said bolt is in retracted position and the outside bolt is be ing protracted, said part being blocked by said projection of the inside bolt when the latter is in protracted position; substantially as described.

a. In a lock, the combination of an outside bolt, an inside bolt, a keyhole for the outside bolt, a key insertible in said keyhole to actuate the outside bolt, means to actuate the inside bolt, and a pivoted ward associated with said outside keyhole and adapted to be raised by engagement with said key, and means on the inside bolt to prevent the raising of said Ward when said inside bolt is in protracted position; substantially as described.

5. In a lock, an inside bolt, an outside bolt, means so connecting said bolts that the protraction of one retracts the other, a keyhole for the outside bolt, a tumbler for the outside bolt, a pivot for said tumbler, and

-' an elbow lever mounted on said pivot, alongside said tumbler and having a ward arm projecting into proximity to said keyhole, and having another arm blocked against upward movement by the inside bolt when the latter is protracted, said last named arm being free of the inside bolt when the latter is retracted; substantially as described.

6. In a look, a latch bolt, a latch bolt hub, a latch bolt yoke having a surface presenting an abutment at the rear end of said yoke, a dead bolt, and a pivoted dog oscillated positively by engagement with said dead bolt into a position in which it lies partially behind said knob yoke, and in contact with the abutment thereof; substantially as described.

In testimony whereof, I have hereunto set my hand on the 20th day of July, l911.

IRVING D. MER-RITT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

